Manifold



A. HOLMES.

MANIFGLD.

APPLICATION HLED DEC. 19, I917.

Patented Apr. 26, 1921.

" 'IUNITED resident of Canton, in the county of in the State of Ohio, have invented new and STATES PATENT- OFFICE;

ARTHUR HOLMES, OF CANTON, OHIO.

MANIFOLD.

useful Improvements in Manifolds, of which the following, taken in connection with the I of particles accompanying drawings, is a full, clear,

and exact description.

This invention relates to certain improvements in internal combustion engines, and pertains more particularly to the inlet manifold or multi-cylinder engines of the type named. v y With the ever decreasing volatilityof the gasolene now being supplied for use in internal combustion engines, and particularly] in cold Weather until the motor warms up, it has been a more and more diflicult problem to prevent one or more cylinders from getting more fuel in proportion to air as compared to other cylinders of the same engine using the same carbureter. This trouble is caused by the fact that the mixture travelmg through the inlet manifold is not a homogenous gas, but a mechanical mixture of unvaporized fuel, vaporized fuel, and air.

It is easy to distribute the air and truly vaporized fuel but the particles of unvaporized fuel, having a greater specific gravity than the former, present a different problem due to the tendency to throw such particles to one side at any turning of a corner in the inlet manifold, where inertia becomes effective, the unvaporized gas or liquid line while the air and gas turn the corner without difficulty. r

This fault in previous inlet manifolds makesit impossible to adjust the mixture at its-origin in the carbureter so as to give the proper mixture in. all cylinders, resulting in non-uniform operation and loss of power over What the engine would ive with proper distribution of Specification of Letters Patent.

in operation at all .times,

bend in the passage and particularly under such condition as the going in a straight ture shown fuel, and in av tendency to' soot the spark plugs and form carbon on the walls of the cylindersgettingth'e Patented Apr. 26, 1921'.

Application filed December 19, 1917. Serial No. 207,868.

\ necessary to produce the required'results is 1' so, great that it reduces the volumetric efficiency of the engine and often results in cracking, or disintegrating the fuel. Other attempts have been made along the, line. of making the path of the gases to the various cylinders equal in length, 'but'designers of this type of manifold failed to take into consideration the fact that at the bends in the passages fuel is thrown out by centrifugal force and due to the shape of the manifold is thrown into one or more cylinders out of proportion to the remaining cylinders.

This invention takes into consideration the inertia of the free fuel and takes advantage of this inertia to obtain equal qualitativedistribution of the mixture with the resultthat the engine is exceedingly smooth the spark plugs are not fouled, and misfiring' and other detrimental results are avoided. 1 l

Other objects 'andadvantages-of the invention relate to the details of construction and operation as will more fully appear from the following description, taken in connection with the accompanying drawings, in which- Figure l'is a side elevation of a'manif'old made in accordance with this invention.

'--.Fig.- 2 is a horizontal sectional view of the same, illustrating a portion of the walls" of cylinders of an internal'combustion englne;

The drawings illustrate a'manifold partlcularly designed for a six-cylinder engine,

but it will be readily understood that this invention can be applied to a multi-cylinder I 1 eing merely illustrative ofone engine of an number of cylinders, the strucembodiment thereof.' 7

As shown, the manifold embodies a main conduit 1-- having at substantially its central point a depending branch 2- adapted to be connected in any suitable manner to a carbureter 3'. The main conduit 1-' 'is provided with a series of branches 4, 5-, -6, p and -'9-, as here illustrated six in number,

' separate sets of three being arranged upon opposite sides of the carbureter branch -2--. Each of these branches communicates through a suitable passageway or inlet with,,-a cylinder of an internal combustion engine- These inlets are numbered, respectively, 11-, -12-, -1a--, -14-- and 15- and extend hrough the walls of respective cylinders, such walls, in this illustration, being indicated as cast en bloc. It will be understood; however, that the construction of the cylinders, their form and arrangement is not material to the invention, although the manifold here illustrated is particularly designed for use with a sixcylinder air cooled engine in which the cylinders are formed separately and spaced some distance from each other.

The branches -4-, 5-- and 6- are in all respects similar to the branches 9, 8- and-7, respectively, and prefer-' y in points -19-- and 20 adapted to act wardly toward the carbureter branch -2 as deflecting surfaces.

The inner walls 21- and -22- of the branches 5 and --8-.likewise 011]?"6 inand symmetrically join the walls "23 and 24 of the conduit 1 along arcuate lines. The outer walls 25- and 26- of these branches are curved substantially in conformity with the inner walls and extend beyond the walls 23 and --24 to sub- ."tantially the central point of the conduit --1--, forming deflecting points or surfaces 27-- and 28 lying midway of the conduit l--- for a purpose hereinafter de.- scribed.

The outer walls 29 and -30- of the conduit -1- are deflected outwardly adjacent the points 2'Z and -28 a distance substantially equal to the projection of the points 27 and '28 into the conduit -1, so that the diameter of the conduit --1 is not diminished beyond the defleeting points 27 and 28-.

The branches -4- and 9- are symmetrically curved inwardly to'unite with the conduit 1 beyond the deflecting points --2T and 28 along arcuate lines. All of the branches preferably terminate in plane surfaces lying substantially parallel with the axis of the conduit -l.

The operation is substantially as follows: When. cylinder A draws its charge, a portion of the fuel in passing point 27- will be thrown by its inertia into branch -5-, due to the position of the deflecting surface '27, the air and vapor all going to branch -4. The fuel thus deposited in branch -5-- will remain thereuntil cylinder B draws its charge.When this takes place, a portion of the free fuel will be thrown by its inertia into the branch 4, likewise due to the projection of the deflecting surface --2'7-, all of the air and vapor going to the branch 5 and its respective cylinder B.

As the division point or deflecting surface 27-- is on the center of the conduit l feeding these two cylinders, the amount of free fuel thrown into branch 4 when branch -5 draws its charge, and into branch 5.when branch -4 draws its charge, should be substantially equal and is in practice substantially equal, thus effecting an equal qualitative distribution to these cylinders. If there is any error or non-uniformity of distribution due to the influence of other cylinders, detected by observation or analysis, this can be corrected by shifting the deflecting surface 27 toward the branch which gets the richest mixture. The operation is the same in connection with branches 9*-' and 8- as in connection with branches --4 and 5.

The points -19 and 20- which divide the mixture going into branches 6- and -7-, respectively, present a somewhat different problem due to the fact that two cylinders draw from the conduit 1 beyond the connection of these branches, and the exact positioning of the points -:19 and 20 will have to be determined "on each design by experiment, but for the particular use for which the manifold here disclosed has been designed the form and arrangement shown upon the drawings has proved correct in detail, and in this form and arrangement the points 19. and -2()-- lie si'ibst ntially in alinement with the apex of the curved wall --16 and, due to the curvature of such wall as well as the curvature of the walls -l7- and ---18-, act to deflect the requisite portions of the free fuel for passage to the other branches of the manifold.

The manifold here shown and described results in a substantially equal qualitative distribution of the mixture to each cylinder and prevents fouling of the spark plugs, carbonizing. the cylinders, misfiring of the engine, and other undesirable effects, and effects a more economical operation with the production of greater engine power, and although I have shown and described one specific construction, form and arrangement as perhaps preferable and peculiarly ap plicable to a six-cylinder engine, it will be readily understood that the form, arrange ment and construction of the manifold may be varied and that the same may be applied to use with any multi-cylinder engine,

municating with the main conduit adjacent the off-set portions, to form deflecting surfaces projecting across portions of the main conduit. r

2. An inlet manifold for multi-cylinder mes comprising amain conduit having i .0 -set portlons and arcuate-shape branc conduits symmetrically merging into the main conduit, and having deflecting surfaces projecting across portions of the main conduit. v

3. An inlet manifold for multi-cylinder engines, adapted to give substantially equal qualitative distribution of fuel to each cyliner, comprising a main conduit and branches 4 communicating with the main coiiduit, the

division line between certain of the branches and the main conduit disposed in the stream of the main conduit to obstruct an areasubstantially proportional to the number of cylinders supplied each side of said division line, the main conduit being offset adjacent said division lineso that the area of the conduit is not reduced.

4.;An inlet manifold for multi-cylinder engines adapted to. give substantially equal qualitative distributlon' of fuel to the cylinders comprising a main conduit, a carburetor branch connected to substantially the central portion of the main conduit, arcuate branch conduitsv communicating with the main conduit and inclined toward the carbureter branch connection, the division line between certain of the branches and the main conduit disposed in the stream of the main conduit to obstruct an area thereof the main conduit being offset adjacent the main division line so that the area of the main conduit is not materially reduced.

5. An inlet manifold for multi-cylinder engines comprisinga main conduit, arcuate branch-conduits for various cylinders, a carbureter branch connecting substantially to the center of said main conduit, the shape of the main conduit and certain of-thesaid branch conduits being such that a section through the main conduit looking straight along inside of the conduit toward said branch will show a line of division across the area of said section the location of said line of division'being such that when projecting on to the area of said section, it will divide the section in proportions according to the number of impulses the engine will draw each side of-said line of div1s'ion, the

two vcenter branch conduits havi their 'inlets coinciding substantially with the circumference of said main conduit, whereby substantially equal qualitative distribution of fuel is given to eachc linder,

6. An inlet manifold or multi-cylinder engines having six cylinders in a row to be supplied from one fuel source comprising a mam conduit, six branch conduits, a versubstantially on the extended center line of said central portion of main conduit, said line of division being adapted to give e ual qualitative distribution between the rst and second, and between the fifth and sixth cylinders, branches for third and fourth cglinders shaped such that the center line of t e two branches forms an arc of a circle cut to the said main conduit, the line ivision between the said branches being located on the surface of said main conduit without projecting into main conduit, said location of line of .division being adapted for equal qualitative distribution as between branch for ,third cylinder, and portion of the main conduit sup lying first and second cylinders, and etween' "branch for fourth .cylinder and portion of main conduit suppl ing fifth andsixth cylinders.

in inlet manifold for multi-cylinder engines embodying a plurality of cylinders ta of in a row, to be supplied from one fuel source comprising a main conduit, a. plurality of branch-conduits communicating therewith,

outlet from said branch conduits, "a distance approximately equal to one half the diameter of said'main conduit, the two central branch conduits communication with said central off-set portion of the main conduit. 8. An inletmanifold for multi-cylinder engines embodyinga plurality of cylinders 7 '"analnconduit.

9. Aninlet manifold fformulti-cylinder engines embodying a plurality ot-cylinders arranged in a row and adaptedto be supplied from 'one fuel source comprising a main conduit, a plurality of branch conduits .in a row, to be supplied from one fuel source in communication with the main conduit, 21 faces extending Fartially across the off-set 10 carbureter conduit connected to substancentral portiono said main conduit.

tially the central portion of said main con- In wltness whereof I have. hereunto set duit, said main conduit having its central my hand this 24th day of November, 1917. portion off-set toward the outlet of the said branch conduits, and two intermediate ARTHUR branch conduits connected to said off-set cen- Witnesses:

tral portion of the main conduit and having Geo. W. BEL EN,

their outer walls constituting deflecting sur- C. Gr, HERBRUCK, v 

